Primary Melanoma of the Penis in 3 Patients With Lichen Sclerosus

Genital lichen sclerosus (GLSc) is associated with squamous cell carcinoma (SCC), although the precise cause is not known. We describe 3 male patients with GLSc and primary penile melanoma. To our knowledge, a possible association between lichen sclerosus and primary penile melanoma has not previously been discussed.

A man in his 50s presented with a firm nodule growing in the left coronal sulcus over 4 months (Figure). Three years earlier, he had been diagnosed with GLSc and unsuccessfully treated with topical steroid preparations of various potencies. Ultimately, he underwent a curative circumcision that same year with histological confirmation of GLSc. Clinically, SCC was suspected, and an excisional biopsy was performed that showed a primary nodular melanoma with a Breslow thickness of 1.2 mm and Clark level 5. Ulceration was seen. Perineural, vascular, and lymphatic invasion were absent. Excision was incomplete, but the patient declined further surgery.

There was some clinical and histologic uncertainty whether the penile lesion was a secondary deposit rather than a primary melanoma. Meticulous clinical examination and extensive initial staging revealed no alternative primary nor metastatic disease. Two months later he developed subcutaneous melanoma deposits on his chest as well as pulmonary and liver metastases. He declined chemotherapy and was treated palliatively until he died.

A man in his 30s presented with a 1-year history of a slowly growing pigmented lesion on the glans of the penis. Clinically, melanoma was suspected, but he also had signs of active GLSc (a tight, scarred frenulum and a constrictive posthitis). An excisional biopsy showed a narrowly excised early radial growth phase mucosal lentiginous melanoma, Breslow thickness of 0.1 mm. He underwent wider excisional surgery and was also circumcised. The foreskin histologic analysis demonstrated GLSc. At last follow-up, he remained alive and well.

A man in his 40s presented with a pigmented macule of the glans penis of uncertain provenance. He had white sclerotic lesions of the glans and foreskin, biopsy of which confirmed GLSc. Histologic analysis of specimens from the pigmented lesion showed early radial growth phase melanoma with a Breslow thickness of 0.44 mm. The melanoma was completely excised, and a circumcision was performed. At last follow-up, the patient remained alive and well.

Male GLSc is a lymphocyte-mediated dermatosis of controversial pathogenesis, but the weight of evidence points to chronic occluded exposure of a susceptible epithelium to urine.¹ It is thought that chronic inflammation and scarring due to GLSc are the drivers to SCC.² The published rates of this complication range from 0% to 12.5%.²

Squamous cell carcinomas constitute 95% of penile cancers. Penile melanoma is responsible for less than 1%³ and typically occurs in the sixth and seventh decades of life; 50% occurs on the glans.⁴ It has an extremely poor prognosis (5-year survival, 31%).⁵ Although UV radiation is important in the pathogenesis of cutaneous melanoma, the cause of genital mucosal disease is obscure.

Primary vulval melanoma has been reported in women with coexisting GLSc. A possible causal relationship has been discussed,⁶ involving a pro-oxidative environment that increases the risk of mutations and disruptions of local mechanisms protecting against “melanocyte carcinogen.” However, the investigators note that the finding may be coincidental rather than causal.⁶

To our knowledge, no cases of concomitant penile melanoma and GLSc have previously been reported. The occurrence of melanoma and GLSc observed in the 3 patients we describe herein may be a coincidence, but in 22 years of providing a dedicated genital dermatology service, these are the only penile melanomas that we have seen. In other words, no penile melanomas have been seen in the absence of GLSc.

Corresponding Author: Nicholas Turnbull, MBChB, FRACP, ICDP-UEMS, Waitemata District Health Board, North Shore Hospital, 124 Shakespeare Rd, Milford, Auckland, New Zealand (drnickturnbull@hotmail.com).

Published Online: November 4, 2015. doi:10.1001/jamadermatol.2015.3404.

Conflict of Interest Disclosures: Drs Turnbull, Shim, Patel, Mazzon, and Bunker have served as consultants to Chelsea and Westminster Hospital NHS Foundation Trust and East and North Hertfordshire NHS Trust. Dr Turnbull is employed by the Waitemata District Health Board, New Zealand.

Funding/Support: This study was supported in part by the National Health Service (NHS) in that patients were seen in the public sector.

Role of the Funder/Sponsor: The NHS had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

Additional Contributions: We are indebted to our consultant pathologist, Nicholas Francis, FRCPath, Imperial College Healthcare NHS Trust, Charing Cross Hospital, London, England; our consultant urologist, Michael Dinneen, MD, FRCSI, Chelsea and Westminster Hospital, London, England; and our consultant dermatopathologist, Florence Derodie, FRCPath, Royal Free Hospital, London, England. We are also grateful to our colleagues at various health care centers for bringing these patients to our attention and providing knowledge and expertise in the individual cases. These persons were not compensated for their contributions.